In most traditional cheese making processes, the whey proteins of milk, although highly nutritious, are removed from cheese curd in a whey drainage step. More recent advances have led to the development of processes for making cheese or cheese-like products that have eliminated the whey drainage step thereby improving both cheese yield and nutrition.
Patent Application WO 00/27214 (Blazey et al) is an example of a process for producing cheese that has eliminated the whey drainage step. This document discloses a method of making cheese in which pH adjusted, concentrated or reconstituted milk is ultra and diafiltered to produce a retentate. The retentate is then supplement with a protein concentrate or isolate; and the resulting mixture is heated to produce a smooth consistency. No enzymes, enzyme cultures, or micro-organisms need be employed by the process.
Other recent developments involve the manufacture of cheese from a milk protein concentrate powder. Such methods have the advantage that cheese manufacture can be uncoupled from supply. That is, because the milk concentrate powder, when compared to fresh milk, can be stored for a significantly longer period without significant degradation (in terms of the ability to be converted to cheese-type products) cheese can be produced on demand, rather than being linked directly to milk supply. Manufacture of cheese from milk protein concentrate powder can also provide cost benefits in transport. Such benefits result from having a product that is of lower weight and volume than milk and that can be used to manufacture cheese.
U.S. Pat. No. 6,183,804 (Moran et al) discloses a two stage process for producing a process cheese-type product. The first stage of the process involves producing a powder milk protein concentrate by ultrafiltration to produce a retentate and then spray drying the retentate. The second stage of the process involves hydrating the powdered milk protein concentrate by mixing the powered milk protein concentrate with water and adjusting the pH of the hydrated milk protein concentrate to between 4.8 and 5.5. Optionally fat is added to the mixture. The mixture is then heated and subjected to shear to form fresh cheese. Flavour additives and emulsifiers are blended with the fresh cheese during a further heating step for a time sufficient to obtain a homogeneous process cheese-type product. Once again no enzymes, enzyme cultures, or micro-organisms are employed and there is no formation or separation of curds and whey. U.S. Pat. No. 6,183,804 also discloses that cream may be used to hydrate the powdered milk protein concentrate.
U.S. Pat. No. 6,242,016 (Mehnert et al) discloses the manufacture of grated Parmesan cheese using an ultrafiltered retentate. The retentate is then fermented followed by the addition of a milk clotting enzyme. The fermented retentate is then subjected to an evaporation step to form a Parmesan cheese with a moisture content of 18 to 24%.
U.S. Pat. No. 4,444,800 (Bixby et al) discloses the manufacture of imitation cheese products of up to 70% total solids (30% moisture). It uses rennet casein and emulsifying salts.
U.S. Pat. No. 5,165,945 (Yee et al) also discloses the manufacture of high solids content cheese. The cheese is made by subjecting milk to ultra and diafiltration, adding a milk clotting enzyme and heating for a sufficient time to coagulate the retentate and followed by the removal of water. Again this is a direct from milk process. The inventors in U.S. Pat. No. 5,165,945 note that excessive solids result in an oily and broken down texture. The document discloses the process of the invention is capable of producing cheese having solids content from 40 to above about 70% by weight. The clotting enzyme is essential to provide such high solids content according to this process. It is generally considered in the art (for example Fitzpatrick J J et al, Practical considerations for reconstituting dairy powders to high solids content in a stirred-tank, Milchwissenschaft 56(9) 2000, pages 512-516) that a high-solids, high-protein recombining process would result in the development of extremely high viscosities during hydration. It is also generally considered that rapid formation of the protein matrix would provide inadequate time for fat dispersion and, simultaneously, fat destabilization would occur as the protein matrix tightened.
It is an object of the present invention to provide a flexible and rapid process for the manufacture of a high-solids (low moisture), high-protein, dairy-based food product such as a hard cheese block, cheese “crumble”, grated/milled hard cheese or dairy-based condiment, which overcomes, at least to some extent, the problems aforesaid, or at least to provide the public with a useful choice.